I've been meaning to post this for a while, but this article over at Zen Habits finally prompted me to write it.
I've gabbed about gas and speeding before, but then it was more about time rather than money.
Before we get too far here though, this is not a debate on American vs. Import vehicles and mileage. Each of us drive our own cars for personal reasons, just as I'm pretty sure I'll be driving a mini van in the near future, each of us has decisions to make when buying our own vehicle. This is intended to save money with your current car, not a "well, you buy a Honda CRX with a 4 cylinder engine and don't use the A/C, you can get 50mph" debate....I'll counter you with I crap more than a Honda CRX and wouldn't fit in it anyway.
But, I'll admit, you won't catch me in a Hummer either.
Once the gas prices started to rise, I remembered a post from my buddies at www.montecarloss.com about how with our V8 gas guzzlers, the best way to drive was to keep the tachometer (the RPM gauge) down below 2,000 RPM. Now, granted, I sold my 6-8mpg Monte Carlo SS, but I wanted to see if it still held true for my 02 Malibu.
So, I'd say for the past 3 months, I've been doing it as religiously as possible. When I accelerate, I keep it pinned as close to 2K as I can. When done right, I could get the car up to 80mph with a long flat stretch of highway if I wanted too.
Now, in city driving, the 2K RPM limit is acceptable because your going from stop to stop, and people usually won't mind you driving like a grandma (you'd be surprised who also does it!). Going uphill, I'll break the rule so I'm not a jerk on the road. Getting on the highway, I break the rule with a passion because I HATE people who don't merge at speed with the highway.
However, once I'm on the highway, I drop the RPMs back to 2K and I can keep up with 65-70mph traffic no problem.
Second to the 2K RPM rule, is learning to slow down with your accelerator. Distant Shoreline and I have talked about this in the past, and the theory basically goes that you use the brakes as little as possible. If your cresting a hill, let off the gas and let the car slow a tad once you get to the top and let it coast down the other side. See a red light that might go green? Let off the gas and coast up to it. See your exit coming up on the highway, and no one behind you? Let off way early and coast up to the light.
The trick here is letting the car's weight do the work. If you want to get to fiddling around with the gears, you could drop into a lower gear and do some engine braking, but that's overkill (and probably brings your RPMs back above 2K). I've toyed with shifting into neutral, but that's more effort than it's worth, especially since I'll forget to put it back into drive when the light goes green.
Third, and this is probably an option most of us do anyway, it hunt for the cheapest gas in town. All gas is regulated by the government and has to pass inspection, so your Quicktrip and Shell commercials about "mine is better than yours" campaigns don't tread too much weight on me. We've got a Costco membership, so we usually fill up there, but there's a 7-11 near daycare that usually has it for the same price. Hy-Vee and Dillons also offer cents off per gallons with a purchase of something. Do your weekly shopping, spend over 100 bucks at Hy-Vee, and get 9 cents off each gallon.
Now, if your buying 20 bucks worth of twinkies to get the discount, your being foolish by spending a lot of money to save money (12 gallons of gas x 9 cents is only 1.08 people!), but if your there and already filling up, take advantage of the offers.
Lastly, drive the speed limit, and keep towards the right so people don't run you over. The fast you go, the higher your RPMs go and the more gas your using. You can find websites that state anything you use over 55mph is to overcome wind resistance and other aerodynamic facts, but use the cruise control and slow your ass down.
How does it add up? Check to see how large your gas tank is. My Malibu has a 14 gallon tank, of which I use 12 gallons. Typically, once the "fill me up" light comes on, you've got roughly 2 gallons of gas left. Before, I'd only get about 220 miles out of my tank because I drove as if I was in the Daytona 500 and careening around the track at 200+ mph.
Driving my grandma ways, the 220 miles has rocketed up to 260 on a regular basis, with a personal high of 287. My goal is to hit the 300 mile mark. I've gone from 18.3mph average to just shy of 24mpg.
It's become my own personal game, every time I get a tank of gas I reset the trip odometer and see if I can get to the 300 mile mark before my idiot light comes on.
Definitely keep up car maintenance too. I'm lazy and get my oil changed at a chain, but I change the air filters myself (Like hell if I'm going to pay them 30 dollars to unscrew a cap, pull out and throw out the old air filter and put in a 10 dollar filter and put it back in again in 2 minutes). But the 25 bucks I pay not to get dirty and climb under the car is worth it.